MASANA'ANTUN NAILAN UKU DA AKA GANI DAGA SARARIN SAMANIYA

Nitrous oxide (N₂O) iskar gas ce mai dumama yanayi wadda ba a cika lura da ita ba amma mai haɗari sosai: gram da gram, tana dumama yanayi sau 273 fiye da carbon dioxide, kuma tana daga cikin manyan abubuwan da ke lalata layin ozone na sararin sama (stratosphere). Noma shi ne mafi girman tushenta daga ayyukan ɗan Adam, kuma shi ne mafi wuyar taƙaitawa. Masana’antu sun fi sauki a gyara — farawa da samar da adipic acid, wanda ake amfani da shi galibi wajen yin nailan.

Wani ƙarin abu da za a iya lalatawa

Samar da adipic acid yana fitar da nitrous oxide kusan ƙwayar halitta da ƙwayar halitta: Kwamitin Gwamnatoci kan Sauyin Yanayi (IPCC) yana amfani da ma’aunin kilo 0.3 na N₂O a kowane kilo na acid. Akwai wuraren samarwa ƙasa da 50 a duniya. Tun daga shekarun 1990, masana’antu da yawa a Amurka da Turai sun sanya na’urori masu amfani da zafi ko sinadarin ƙara sauri (catalyst) waɗanda ke lalata fiye da kashi 90% na wannan iskar gas. Har yau wannan fasaha tana da riba.

Yanzu ƙasar Sin ce ke kan gaba wajen samarwa a duniya. Wasu masana’antun ƙasar Sin a da sun lalata kusan dukkan N₂O ɗinsu, ana biyan su da takardun bashin carbon (carbon credits) daga wani shirin Majalisar Ɗinkin Duniya, wato Clean Development Mechanism. Tsarin ya haifar da akasin abin da ake so: sayar da takardun bashin ya zama mafi riba fiye da sayar da adipic acid, abin da mai yiwuwa ya ƙara yawan hayakin duniya. A shekarar 2011, Tarayyar Turai ta haramta waɗannan takardun bashi a kasuwar carbon ɗinta, kuma rage hayakin ya daina kawo riba. Tun daga lokacin, babu wanda ya sani ko masana’antun har yanzu suna lalata nitrous oxide ɗinsu.

Karanta iskar gas a cikin hasken rana

Nicholas Balasus da Daniel Cusworth, na Carbon Mapper, wata ƙungiya da ake ɗaukar nauyinta ta hanyar gudummawa a Pasadena, California, sun je su duba daga sararin samaniya. Nitrous oxide yana shanye ɗan kaɗan na hasken rana a wasu tsawon igiyoyin haske na musamman a cikin infrared mai gajeren zango (shortwave infrared), tsakanin nanomita 2,050 da 2,350. Tauraron ɗan Adam Tanager-1 yana ɗaukar wannan haske dalla-dalla, da pixels masu fadin mita 30.

Ga kowane pixel, tawagar ta kwatanta bakan haske (spectrum) da alamar shanyewa da ake tsammani daga N₂O, abin da ke bayyana ƙarin iskar gas a cikin ginshiƙin iska. Haɗa dukkan ƙarin iskar gas da ke cikin hayaki da kuma haɗa shi da saurin iska yana ba da adadin fitarwa. Wannan hanya ta riga ta ci jarrabawar makafi (blind tests) game da methane.

Hayakin nitrous oxide a saman masana’antun adipic acid na Taiyuan, Dezhou da Chongqing, a lokacin bazara na 2026; kibiyoyin suna nuna iska. — Figure 1, Balasus & Cusworth (2026), arXiv:2610.07542.

Masana’antu uku, tan 680,000

Daga wucewa guda ɗaya-ɗaya a lokacin bazara na 2026, marubutan sun ƙiyasta:

• Taiyuan: kusan tan 2.2 na N₂O a kowace awa;
• Dezhou: kusan tan 19.6 a kowace awa;
• Chongqing: kusan tan 55.6 a kowace awa.

A cikin shekara guda, wannan ya kai tan miliyan 0.68. Musamman ga Dezhou da Chongqing, waɗannan adadi suna nuna cewa rage hayakin yana da iyaka, idan aka yi la’akari da yawan acid da ake tsammanin masana’antun suna samarwa.

Don tabbatar da cewa hoto guda bai zama kuskure na kwatsam ba, sun duba da EMIT, wata na’ura mara ƙarfin ji kamar ta farko da ke cikin Tashar Sararin Samaniya ta Kasa da Kasa. Idan aka ɗauki matsakaici na kwanaki da dama a 2025 da 2026, tana ba da tan 1.9 a kowace awa ga Taiyuan da 19.2 ga Dezhou; wucewa guda a saman Chongqing a watan Afrilun 2024 ta ba da kusan 60. Dukkansu sun yi daidai.

Wani gibi a cikin lissafin duniya

Ƙiyasin baya-bayan nan na “ƙasa-zuwa-sama” (bottom-up) na hayakin N₂O daga adipic acid a duk duniya ya kasance ƙasa da rabin jimillar waɗannan masana’antu uku kaɗai. A cewar marubutan, mai yiwuwa hakan ya faru ne saboda tsoffin bayanan samarwa da rashin tabbas game da rage hayaki — wanda ke nufin cewa rawar da wannan masana’antar ke takawa a cikin lissafin nitrous oxide na duniya mai yiwuwa an rage shi.

Idan aka canza su da ma’aunin daidaito na Hukumar Kare Muhalli ta Amurka (EPA), kawar da waɗannan hayaki zai zama kamar rufe tashoshin wutar lantarki na gawayi 49 ko cire motoci miliyan 43 masu amfani da fetur daga hanyoyin Amurka na tsawon shekara guda.

Lissafin bai cika ba. A wani wuri, Pingdingshan, hayakin yana zuwa yana tafiya tsakanin ziyarori, don haka marubutan ba su sanya shi cikin jimillar su ba. Aƙalla wasu masana’antun adipic acid shida a ƙasar Sin ba a auna su ba tukuna, kuma ba a san ainihin wurarensu da tabbas ba. Ganin cewa samarwa tana ci gaba da ƙaruwa a ƙasar Sin kuma akwai mafita a shirye, marubutan suna ganin rage waɗannan hayaki a matsayin muhimmin buri na gaggawa ga yanayi.